<template>
  <div class="login_container">
    <div class="login_box">
      <!-- 头像区 -->
      <div class="avatar_box">
        <img src="../assets/logo.png" alt="" srcset="" />
      </div>
      <!-- 登陆表单区 -->
      <el-form ref="loginFormRef" :model="loginform" :rules="loginFormRules" label-width="0px" class="login_form">
          <!-- 用户名 -->
        <el-form-item prop="username">
          <el-input v-model="loginform.username" prefix-icon="el-icon-user-solid" placeholder="用户名"></el-input>
        </el-form-item>
        <!-- 密码 -->
        <el-form-item prop="password">
          <el-input type="password" v-model="loginform.password" prefix-icon="el-icon-lock" placeholder="密码"></el-input>
        </el-form-item>
        <!-- 按钮区域 -->
        <el-form-item class="cbtn">
          <el-button @click="login" type="primary" plain>登陆</el-button>
          <el-button @click="resetLoginForm" type="info" plain>重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
export default {
    data () {
        return {
            // 登陆表单的数据绑定对象
            loginform: {
                username: 'admin',
                password: '123456'
            },
            // 表单验证
            loginFormRules: {
                username: [
                    { required: true, message: '请输入登录名称', trigger: 'blur' },
                    { min: 3, max: 10, message: '长度在 3 到 10 个字符', trigger: 'blur' }
                ],
                password: [
                    { required: true, message: '请输入密码', trigger: 'blur' },
                    { min: 6, max: 15, message: '长度在 6 到 15 个字符', trigger: 'blur' }
                ]
            }
        }
    },
    methods: {
        resetLoginForm () {
            // $refs是一个对象对象下有我们生成的loginFormRed实例化表单对象
            this.$refs.loginFormRef.resetFields()
        },
        login () {
            this.$refs.loginFormRef.validate(async valid => {
                if (!valid) return false
                const { data: res } = await this.$http.post('login', this.loginform)
                if (res.meta.status !== 200) return this.$message.error('登陆失败')
                this.$message.success('登陆成功')
                // 1.将登录成功之后的token, 保存到客户端的sessionStorage中(localStorage是持久的存储机制sessionStorage是会话存储机制网页打开的时候生效)
                //  1.1项目中出了登录之外的其他API接口，必须在登录之后才能访问
                //  1.2 token 只应在当前网站打开期间生效，所以将token 保存在sessionStorage 中
                // window对象下的方法下的api设置保存token
                window.sessionStorage.setItem('token', res.data.token)
                // 2.通过编程式导航跳转到后台主页，路由地址是/home
                this.$router.push('/home')
            })
        }
    }
}
</script>

<style lang="less" scoped>
.login_container {
  background-color: #2b4b6b;
  height: 100%;
}
.login_box {
  width: 450px;
  height: 300px;
  background-color: #fff;
  border-radius: 3px;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  .avatar_box {
    height: 130px;
    width: 130px;
    border: 1px solid #eeee;
    border-radius: 50%;
    padding: 10px;
    box-shadow: 0 0 20px #ddd;
    position: absolute;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: #fff;
    img {
      width: 100%;
      height: 100%;
      border-radius: 50%;
      background-color: #eee;
    }
  }
}
.login_form{
    position: absolute;
    bottom: 0;
    width: 100%;
    padding: 0 20px;
    box-sizing: border-box;
}
.cbtn{
    display: flex;
    justify-content: flex-end;
}
</style>
